1. Field of the Invention
This invention relates generally to therapeutic and rehabilitative apparatus for stretching and exercising a shoulder, and more particularly to an apparatus which self-assistedly provides shoulder passive range of motion therapy for a user or patient.
2. Description of Related Art
There are several methods of accomplishing therapeutic range of motion associated with rehabilitation of an injured or recent surgery of a shoulder area of a patient. Active range of motion (AROM) is utilized by a patient who is able to move under his or her own power without assistance. Assisted active range of motion (A-AROM) is utilized by a patient utilizing his or her own body weight to augment the range of motion therapy. Passive range of motion (PROM) is motion provided for the patient by a therapist or attendant. Lastly, Continuous passive range of motion (C-PROM) is associated with providing a device which implements PROM for a preset amount of time.
PROM is typically prescribed as an initial mode of therapeutic intervention for patients who experience a range of motion limitation or otherwise require passive range of motion to regain functionality. The only home exercise available is the Codman's exercise in which the patient bends at the waist and allows the affected upper extremity to passively hang down. The patient then noves his body to passively swing the arm.
In the clinic, PROM has been performed in one of two ways, either by a therapist or through the use of a standard pulley system. PROM performed by a therapist is considered to be the “gold standard” or the very best form of range of motion therapy, but is not optimal for at least two reasons. First, the therapist can only perform this therapy on a limited time basis, typically one hour per session and perhaps only a few times a week for a limited time period due to insurance reimbursement limitations. Moreover, due to patient anxiety, full relaxation may not be possible during PROM. The automatic self-preserving guarding or hesitation can cause increased pain and potential damage to recovering tissue.
The use of PROM by a standard pulley system is somewhat controversial. Some physicians and therapists believe that PROM can be performed utilizing standard pulley systems although there is a lack of evidence to support that position. In fact, PROM by standard pulley system implementation averages 17.6% of the maximum muscular activity as compared to 5% from therapist-assisted PROM.1 With a standard pulley system, the patient grasps the handle of the pulley once this occurs, muscles of the hand, wrist, forearm and the shoulder are facilitated. 1 Dockery, M I, Wright, T W, and Lastayo, P., Electromygrophy of the shoulder, an analysis of passive modes of exercise. Orthopedics 11:1181, 1998
A number of patented prior art devices attempt to provide some level of additional passive or active range of motion but fail to disclose the full benefits achieved by the present invention. Those references are summarized herebelow:
U.S. Pat. No. 3,892,230 to Baker, et al. teaches an orthopedic device for loosening a stiffened shoulder joint. The non-portable device uses a sling for holding the mark which is not locked in place and could be unsafe for use by a postoperative patent. A portable doorway and floor stand exerciser for use by wheelchair occupants is taught by Kelly in U.S. Pat. No. 5,048,825. The device is primarily used to develop strength and not for increasing range of motion of the shoulder.
Donovan, et al. discloses a passive anatomic shoulder exerciser in U.S. Pat. No. 5,179,939 and, while providing PROM, would require an attendant and electrical power. U.S. Pat. No. 5,501,656 to Homma, et al. teaches an arm motion support apparatus which is not designed to increase range of motion but to decrease gravity of the affected area allowing the patient to gain freedom of motion.
Fontanna, et al. teaches a shoulder stretching and rotation machine in U.S. Pat. No. 5,520,615 wherein physical therapy of the shoulder joint through passive internal and external rotation of the shoulder is provided. A device for use on a traction machine to treat carpal tunnel syndrome is taught by Repice, et. al. in U.S. Pat. No. 5,632,726. Harmon teaches a resistance exercise apparatus in U.S. Pat. No. 5,913,749; however, this device does not provide PROM and is not a pulley system. Pape teaches a non-passive resistance exercising apparatus in U.S. Pat. No. 6,530,868 and U.S. Pat. No. 6,705,974 to Tardif teaches a device developed for active assistive stretching of the lower extremities and could not safely perform PROM.
The present invention is associated with the newest range of motion form, i.e. self-assistive passive range of motion (SA-PROM) wherein a device is used to help the patient independently perform true PROM. The present invention is the only apparatus known to accomplish the SA-PROM form of shoulder therapy.
The present invention provides an apparatus which enables a patient to perform safe, self-assisted passive range of motion (SA-PROM) either in a clinic or at home after proper educational use of the apparatus. Thus, the patient may safely perform SA-PROM which will typically greatly increase the frequency and time or duration of therapy and thus improve the overall outcome while decreasing discomfort for the patient. In use, the present system includes an attachment preferably to the top edge of a door; the patient rests the affected forearm in an elongated forearm support which is secured in place preferably by releasable straps. The forearm support enables the elbow to be straight, decreasing the patient's ability to use the bicep to help facilitate motion. The patient then pulls down on a handle connected at one end of an elongated main rope with the unaffected arm. Slow, gentle steady movement of the affected arm by controlled motion of the handle is thus achievable while also reducing the level of discomfort experienced by the patient.